That’s the pattern the New York business has followed over the past 14 months since the media mogul took a 10 percent stake in the weight loss company — and joining its board and becoming its dieter-in-chief.

On Thursday, Weight Watchers International unveiled a new ad campaign, “Live Fully,” and dropped some big news on America: Oprah has lost more than 40 pounds since she began the program in August 2015!

Winfrey boasts that she slimmed down while following her Weight Watchers plans that she said allowed her to eat whatever she wanted, including tacos, pasta and bread.

“Weight Watchers is a lifestyle,” she said.

Shares spiked as much as 17 percent during the day before giving up some of the gains and closing up 5.3 percent, to $11.08.

It’s not the first time Weight Watchers’ stock has gotten fat news of Winfrey’s dieting victories. But the stock spikes, like Winfrey’s previous weight losses, were short lived.

Weight Watcher’s shares are still down roughly 50 percent this year.

Winfrey paid $43.2 million on Oct. 19, 2015, for 6.4 million shares — or $6.79 a share. The stock doubled that day, reached $26.61 within a month — but then collapsed under the weight of disappointing sales.

A lot is riding on the new ad campaign as Weight Watchers typically gets 40 percent of its new members in January and February, according to research analyst John Tomlinson of M Science.

But overall Oprah has been a boon to the company. This year, membership has grown on average by 11 percent compared with declines as much as 20 percent over the previous eight quarters, Tomlinson said.